<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        b{
            font-weight: normal;
        }
        .bold{
            font-weight: bold;
        }
        .italic{
            /*斜体*/
            font-style: italic;
        }
        i{
            font-style: normal;
        }

        div{
            /*复合属性
          font:font-style font-weight font-size font-family
          */
            font: italic bold 24px '宋体';
            /*
            省略font-style font-weight
            font:24px '宋体'
            */
        }
    </style>
</head>
<body>

<div>演示字体属性</div>

<span class="bold">我是加粗的span</span>
<span class="italic">我是斜体的span</span>
<b>我是加粗文字</b>
<i>我是斜体的文字</i>

]
</body>
</html>